Adenosine deaminase acting on RNA (ADAR)

Adenosine deaminase acting on RNA refers to a family of evolutionarily conserved enzymes known as ADARs that catalyze the conversion of adenosine to inosine within double-stranded regions of cellular RNAs—a process called A-to-I editing. This modification alters base-pairing properties and can recode protein-coding sequences or affect noncoding regulatory elements. In humans there are three main isoforms—ADAR1 (with p110 constitutive and p150 interferon-inducible forms), ADAR2 (constitutively expressed), and catalytically inactive ADAR3—each with distinct tissue distributions and substrate preferences. These enzymes play critical roles across diverse biological processes including nervous system development/functionality, hematopoiesis, innate immunity discrimination between self/non-self nucleic acids via MDA5 pathway modulation, apoptosis regulation through mRNA splicing/translation changes, viral persistence control via viral genome editing/mutation rates modulation—and more recently have been implicated as promising therapeutic targets for cancer immunotherapy as well as genetic/neurodevelopmental/cardiovascular disorders when dysregulated[1][3][4][5].

Other names

Double-stranded RNA-specific adenosine deaminaseAdenosine deaminases acting on RNAADAR1ADAR2ADAR3

Drugs or interventions targeting this molecule would typically act by inhibiting or enhancing its enzymatic activity—specifically the conversion of adenosine to inosine in double-stranded RNAs—or modulating its interaction with other proteins involved in immune signaling or microRNA processing.